There are a number of diseases in which the bone marrow is defective, such as aplastic anemia, some forms of leukemia, and deficiencies in the bone marrow caused by cancer treatments with drugs and irradiation. The treatment of choice for these diseases is bone marrow transplantation, provided a genetically compatible donor can be found. For instance, bone marrow transplants are significantly reducing the death toll from childhood leukemias.
Bone marrow, also called myeloid tissue, is a soft, gelatinous tissue that fills the cavity of the bones. Human bone consists of a hard outer cortex and a soft medullary cavity that contains bone marrow. Bone marrow consists of stroma, or supporting tissues which have spaces packed by blood cells. Bone marrow is either red or yellow, depending upon the preponderance of vascular (red) or fatty (yellow) tissue. In humans, the red bone marrow forms all of the blood cells with the exception of the lymphocytes, which are produced in the marrow and reach their mature form in the lymphoid organs. Yellow bone marrow serves primarily as a storehouse for fats, but may be converted to red marrow under certain conditions, such as severe blood loss or fever. At birth, and until about the age of seven, all human marrow is red, as the need for new blood formation is high. Thereafter, fat tissue gradually replaces the red marrow, which in adults is found in the vertebrae, hips, breast bone, ribs, and skull, and at the ends of the long bones of the arms and legs, other cancellous, or spongy bones, and the central cavities of the long bones. In mammals, blood formation in adults takes place predominantly in the marrow. Because the white blood cells produced in the bone marrow are involved in the body's immune defenses, marrow transplants have been used to treat certain types of immune deficiencies. The sensitivity of marrow to damage by radiation and some anticancer drugs accounts for the tendency of these treatments to impair immunity.
Bone marrow transplants can be divided into three groups according to the source of the marrow for transplantation. They are called autologous, syngeneic, or allogeneic. Autologous transplantation means that the bone marrow has been received directly from the recipient, and will be an exact genetic match. A syngeneic transplant comes from an identical twin of the recipient and will also be an exact genetic match. However, for allogeneic transplants, the bone marrow is provided by another person, and the possibility of exact genetic matching is very low.
It is reported that approximately 12,000 bone marrow transplants were performed in 1992, approximately half of which were allogeneic and half autologous. Autologous transplantation has grown significantly during the past several years as improvements in procedures are made. The number of patients receiving allogeneic transplants is also rising due in large part because donor registries have increased the number of readily available donors. Advances in bone marrow transplantation techniques will likely continue to expand the use of the bone marrow transplant procedure.
Generally, the recipient's sibling or parent will serve as the best source as the donor because of the high possibility of genetic matching. However, there are many cases where neither the parent nor the sibling will be a compatible genetic match for the recipient. There has been a recent increase in the use of bone marrow from unrelated donors which can provide genetic compatibility between the donor and recipient. This increase has been made possible through the existence of large bone marrow registries, such as the National Marrow Donor Program, and the American Bone Marrow Donor Registry. The drawback to these registries are the insufficient number of donors that genetically match closely enough with potential recipients to be of use.
The success of the bone marrow transplantation technique depends heavily on genetically cross-matching the donor marrow cells to those of the recipient to prevent rejection. There is a significant tendency for the recipient patient to reject an allografted marrow because parts of the donor marrow will attack their new host. There is an additional hazard because immune system cells in a marrow graft can react against the patient's tissues, causing serious and sometimes fatal graft versus host disease. The ability to accept a bone marrow transplant (graft) from a donor, is dependent on the recipient sharing all of the donor's histocompatibility genes. To avoid graft versus host rejection in the past, special immunosuppressive treatment has been given. The use of monoclonal antibodies to selectively remove harmful lymphocytes from the donor marrow has been successful in some cases to prevent graft versus host disease. However, the risk remains that unless the bone marrow source is from the patient himself, an identical twin, sibling, parent, or other genetically compatible donor, that the bone marrow transplantation cannot take place because it will result in graft versus host rejection, and the failure of the treatment, and possibly the death of the recipient.
Therefore, there is a significant need to collect and store genetically compatible bone marrow for use in cases where bone marrow transplantation is necessary to save the life of an individual. Because of the significant possibility that a donor cannot be found which is a close genetic match to the recipient, there is a need to collect and store an individual's own bone marrow while that individual is still healthy. If this is done, there will be a complete genetic match, and the dangers of graft versus host rejection will be eliminated which increases the success of the treatment.
The collection of bone marrow for transplantation purposes is usually accomplished by inserting a needle into a donor's hip or pelvic bone. Several small incisions are made in the pelvic area, and the needle is inserted through these incisions approximately 25 to 30 times to withdraw the bone marrow from the bones. The extraction process typically lasts at least one hour or more, or until approximately 500 to 1000 milliliters of the donor's marrow is withdrawn.
The donor will fully recover in approximately a few weeks when all the donated marrow has been replaced within the body. However, the extraction process is painful and there is typically soreness around the incisions until healing can occur. Typically, the donors also feel fatigued for some time after the procedure. The side effects to having donated bone marrow can vary from donor to donor. Infection from the incision is always a possibility. Additionally, blood loss can also occur, and proper medical attention is required. It is recommended that donors routinely store supplies of their own blood for infusion during and after the extraction procedure in cases of emergencies.
Bone marrow can be obtained through biopsy or aspiration from the sternum or the calvarium in adults, and in long bones, such as the femur and tibia, in adolescents. Biopsy needles for extraction of solid bone marrow are known. Examples of such biopsy needles are U.S. Pat. Nos. 2,991,692; 2,426,535; 2,496,111; 4,272,676; 4,266,555; 4,543,966; 4,487,209; 4,840,184; and 4,922,602, which show the overall structure and orientation of the components. Needles used for aspiration of liquid bone marrow are disclosed in U.S. Pat. No. 4,469,109. Needles designed to both biopsy and aspirate bone marrow are disclosed in U.S. Pat. Nos. 2,496,111; 3,587,560; 5,012,818; and 5,357,974.
There is a need for bone marrow extraction techniques that avoid the considerable inconvenience, discomfort, and pain due to current bone marrow extraction procedures and aspiration methods. Therefore, there is also a need to provide a method and apparatus to obtain both solid and liquid bone marrow from a donor with minimal intrusion and pain. There is also a need for the bone marrow to be stored for later use and is accomplished with relative ease.